The invention relates to flexible magnetic disks and more particularly to the standard write enable notch found on the jacket edge of these flexible magnetic disk assemblies.
The flexible magnetic disk popularly known as a "Diskette" or "Floppy" disk, has become the most popular means of storing, in binary form, files used with word processors and personal computers. A necessary feature of the floppy disk drives used to read and write the binary information on the flexible magnetic disk is that of providing a means of protecting data resident on a disk from accidental erasure or re-recording.
The accepted method for accomplishing this write protection is for the manufacturers of the flexible magnetic disks to provide a specifically located and dimensioned notch on the edge of the jacket enclosing the magnetic disk, and the manufacturers of the magnetic disk drives provide a means of sensing the presence of this notch before enabling the erase or record functions.
The most popular method used by the disk drive manufacturers to accomplish notch sensing is by use of a microswitch and arm as described and shown in FIG. 2 of U.S. Pat. No. 4,040,106 entitled "Flexible Magnetic Disc Drive Apparatus", by Harold C. Medley, although other sense techniques such as light sensing are currently in use.
To preclude the inadvertent loss of recorded data, operators of systems utilizing flexible magnetic disks cover the notch with an adhesive tape. When operators wish to add new data to the magnetic disk or alter or remove existing recorded data they must peel off this adhesive tape before their system will enable the erase or write functions.
The typical operator performs this application and removal of adhesive tape many times on their Floppy disks and as a result the adhesive makes a sticky mess on the jacket of the disk or depending upon temperature, time, humidity and other environmental factors, the adhesive either sticks so tenaciously it is difficult to remove the tape or sticks so poorly that the tape falls off.